There are several ways to form text for display. A segment display uses lines, while a dot-matrix display uses a grid of dots, and both of these are seen in LCD, LED, VFD, and vane/disc types. For split-flap displays, the characters or words are pre-printed, and for nixie tubes the shapes are also pre-formed. In any case, the display elements are controlled by electronics which activate them in the correct physical and temporal sequence to show the desired information.

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LED text displays refer to types that are specialized and limited to display of alpha-numeric characters. Most types display either one character or a group of characters. One character is generally displayed by a matrix of LED's, or by a set of segments.

An eggcrate display is one older method of displaying an alphanumeric character. It consists of a matrix of incandescent light bulbs. A foam rubber mask with an array of holes surrounding the bulbs is attached to the display, causing it to resemble an egg crate.

Some eggcrate displays use a complete 5×7 matrix for each digit, permitting the display of nearly all alphanumeric characters. Other types display only numeric characters and optionally a dollar sign. This type of eggcrate display is popularly used for sports scoreboards.

Eggcrate displays have been used on many game shows to display contestants' scores and/or for countdown clocks because other types of displays, such as LEDseven-segment displays, were prone to being washed out by bright studio lights. Though they continued to see extensive use well into the late 1990s, many shows began adopting LCDs in the 2000s.

A vane display is a type of 7-segment display. Unlike LED and VFD segmented displays, vane displays are composed of seven physical surfaces, typically painted white, but occasionally other colors, such as yellow or fluorescent green. If a segment is to be displayed as "off", it will be rotated so that its edge faces forward, with the painted surface pointing away and not visible. A segment that is to be displayed as "on" will be rotated so that the painted surface is shown.